Mechanical-electrical drive for bobbin-spinning machines



Patented Nov. 23, 1943 MECHANICAL-ELECTRICAL DRIVE FOR BOBBIN-SPINNING MACHINES Alfred Friedericli, Berlln-Wilmersdorf, and Reinhold Wieland, Berlin-Karlshorst, Germany; vested in the Allen Property Custodian Application June 21,

In Germany 3 Claims.

Our present invention relates to a driving device for bobbin-spinning machines for the production of rayon and more particularly to a means for adjusting the peripheral speeds of the bobbins by a mechanical-electrical driving device.

In the known processes for making rayon the spinning liquid is extruded in constant quantity through a system of fine perforations. In order that the thickness of the threads may be invariable it is necessary to withdraw them from the spinning nozzle at a constant speed. In many cases this draft is provided by winding the thread on a cylindrical bobbin of a certain diameter. In order that the draft, or speed of winding, may remain the same as the diameter of the coil on the bobbin increases, there have been used hitherto chiefly mechanical drives, so-called conoidal drives, in which a driving belt is caused to slide on two opposed conical belt pulleys, whereby a gradual and constant diminution of the number of revolutions per minute of the driven shaft is produced and therewith a diminution of the speed of rotation of the bobbin, such that the draft on the thread remains constant.

The numerous inconveniences and the unreliability of this mechanical drive has prompted the substitution for it of mechanical-electrical drive. In the case of bobbin-spinning machine operating on the double bobbin system, wherein for each spinneret there are two bobbins of which the spindles are driven in pairs by separate shafts, there have been used for this purpose two motors having controlled variable speed for the driving of each bobbin system. The speed of these motors is changed mechanically through a continuously driven switch by actuation of a control shaft which, for example, shifts the brushes of a three-phase motor. This control device, as well as the other auxiliary devices of the machine, for instance the thread laying device (swinging thread guide), are driven through a third motor of constant speed.

It is an object of our present invention to provide a mechanism which positively couples with each other the switching devices necessary in a drive of the kind described in such a manner that faulty switchings are eliminated.

A further object is the provision of a spinning machine in which supervision becomes as simple as possible, with a minimum of manipulations.

Further objects of the invention reside in details of construction and in an arrangement of parts, as will become more apparent as the following specification proceeds.

1938, Serial No. 215,072

June 29, 193'! Reference is made to the accompanying drawing in which:

Fig. 1 is a diagrammatical plan view of a device according to this invention; v

Fig. 2 shows a means for returning the driving motors to the initial speeds when the motors are determined initial number of revolutions (Figure 2).

Referrring now to Figure 1 the bobbins b1 and b: are positioned on the spool shafts s1 and sz, respectively. The spool shafts are alternately driven by the driving shafts 101 and we through the gears n and m, respectively. The driving shafts 1121 and we are themselves driven by the motors M1 and Mn, respectively through the belts k1 or k: as the case may be. These motors are variable speed motors, for instance threephase alternating current motors, the speed of which can be continuously varied by means of a separate drive It; or Rn. This variation of the speed is brought about by a slow progressive rotation of the switch shaft a on which is iixe'd a disc b turning behind the stationary pointer 2. As already mentioned above the rate of revolutions of the driving motors may be influenced by shifting of the brushes of these motors. The

. brushes are arranged as usual on the periphery of the collector and may be shifted to a certain degree in both directions by means of a segment. In order to produce this shifting various means may be employed for instance an auxiliary shaft (a in Figure 2) which by means of a cogged wheel 1 fixed thereon engages a cogged wheel segment firmly united with the brush fasteners. In consequence one or a part of one revolution of the shaft (1 and at the same time of the disc or pulley 1) corresponds with a certain predetermined shifting of the brushes. Since, however, each position of the brushes corresponds with a certain number of revolutions of the motor it is obvious that it is possible as shown in Figure 2 to indicate the corresponding number of revolutions directly on the periphery of disc I).

The shaft a is driven slowly by means of a separate motor Mm which by means of a suitable on gear drives the gear wheels P which are in'constant engagement. The large wheel 1" of this drive is mounted free on its shaft. Its movement is transmitted through a coupling m, to a chain Kr, Kn, respectively, which drives a corresponding wheel R: or Rn. By means of rods hi and he having handles a: and as, respectively, and actuating the control of the motor switch Nr, Nn, respectively, and at the same time connected with the sliding clutch in or 9: as the case may be, a motor, for instance is started and simultaneously and automatically therewith a clutch v: is brought into engagement and thereby the drive Rn is started.

80 also when the motor, for instance Mr, is cut out, a clutch in is brought out of engagement and thereby adJustment of the speed of the corresponding motor is interrupted.

The disengagement of the clutch in or v: has automatically another consequence, which will be explained with reference to Figure 2. The control shaft is subject to a load lwhich acts on the disc b through a cord 1 running over spools u or is. The eilect of the load isto urge the shaft a in the direction opposite to the torque applied by the gear F through the chains Kr or Kn, namely, in the anti-clockwise direction, so as to bring it back into its initial position, which is determined by the abutment of the adjustable stop d fixed to the disc against the stationary stop 0. At the moment when by disengaging the coupling D1 or m, the load 1 is free to act, the control shaft a returns to its initial position.

What we claim is:

1. In a rayon spinning machine operating on the double-bobbin system, in combination, a pair of bobbins fixed on a common shaft, electrical means for driving said shaft, a switch for said driving means, control means connected with said switch for progressively diminishing the speed of the driving means while said switch is closed and means, operating when said switch is opened, to place the driving means in a condition. where upon again closing the switch, the driving means will run at its original speed.

2. In a rayon spinning machine operating on the double-bobbin system, in combination, a pair of bobbinsiixed on a common shaft, a threephase electric motor for driving said shaft, a switch for said motor, a rotatable control disk in fixed relation to the brushes of said motor, a second motor for driving said control disk to shift the brushes and thereby diminish progressively the speed of said three-phase motor, means connected with the switch for engaging said second motor with said control disk to diminish progressively the speed of the three-phase motor, when the switch is closed, said last-named means operating to disengage said second motor from said control disk when said switch is opened, and a weight aillxed to said control disk operating, when said switch is opened, to return the control disk to its initial position.

3. In a rayon spinning machine operating on the double-bobbin system, in combination, a pair of bobbins fixed on a common shaft, a threephase electric motor for driving said shaft, a switch for said motor, a rotatable control disk in fixed relation to the brushes of said motor, a rigid pointer cooperating with said control disk, a second motor for driving said control disk, a clutch connecting said second motor and said control disk, means connected with the switch for engaging said clutch whereby the position of the brushes is shifted to diminish progressively the speed of the three-phase motor when the switch is closed, said last named means operating to disengage said clutch when said switch is opened, and a weight affixed to said control disk operating, when said switch is opened, to return the control disk to its initial position.

ALFRED FRIEDERICH. REINHOLD WIELAND. 

